Quantification of salivary magnesium using a microfluidic paper based analytical device (μPAD)

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Cactus Cladodes Opuntia or Nopalea and By-Product of Low Nutritional Value as Solutions to Forage Shortages in Semiarid Areas

Simple Summary In the different livestock production systems, forage is the main feed resource. However, the availability and quality of the forage fluctuate throughout the year due to variable environmental conditions, such as temperature, humidity, location, or lack of rainfall. In semiarid regions, this fact is even more critical. The option for forage plants adapted to the semiarid climate, such as cactus cladodes, becomes indispensable for the sustainability of the systems. Nonetheless, it is necessary to combine the cactus with high-fiber-content feeds (silage, hay, and agroindustry residues, among others) to increase fiber contents in the diet to promote ideal rumen conditions. Based on the knowledge that cactus cladodes (Opuntia spp. and Nopalea spp.) are one of the most viable crops in semiarid regions, the association with a by-product rich in NDF proves to be a more feasible alternative in terms of price and availability, with the producer making the final decision. We aimed to evaluate the effect of the cactus cladodes Nopalea cochenillifera (L). Salm-Dyck. (NUB) and cactus cladodes Opuntia stricta (Haw.) Haw. (OUB), both combined with sugarcane bagasse (SB) plus urea, Tifton hay (TH), corn silage (CS), and sorghum silage (SS) plus urea on nutrient intake and digestibility, ruminal dynamics, and parameters. Five male sheep, fistulated in the rumen, were assigned in a 5 x 5 Latin square design. The NUB provided a higher intake of dry matter (DM) and any nutrients than SS. TH provided larger pools of DM and iNDF. The OUB and CS provided a higher DM degradation. CS provided a higher NDF degradation rate. OUB provided a lower ruminal pH. Depending on the collection time, the lowest pH value was estimated at 3.79 h after the morning feeding. There was an interaction between treatments and collection time on VFA concentrations. Due to the high degradation rate, greater energy intake, less change in rumen pH, greater volatile fatty acid production, and feasibility, we recommend using cactus associated with sugarcane bagasse plus urea in sheep diets

Analogues of Marine Guanidine Alkaloids Are in Vitro Effective against Trypanosoma cruzi and Selectively Eliminate Leishmania (L.) infantum Intracellular Amastigotes

Synthetic analogues of marine sponge guanidine alkaloids showed in vitro antiparasitic activity against Leishmania (L.) infantum and Trypanosoma cruzi. Guanidines 10 and 11 presented the highest selectivity index when tested against Leishmania. The antiparasitic activity of 10 and 11 was investigated in host cells and in parasites. Both compounds induced depolarization of mitochondrial membrane potential, upregulation of reactive oxygen species levels, and increased plasma membrane permeability in Leishmania parasites. Immunomodulatory assays suggested an NO-independent effect of guanidines 10 and 11 on macrophages. The same compounds also promoted anti-inflammatory activity in L. (L.) infantum-infected macrophages cocultived with splenocytes, reducing the production of cytokines MCP-1 and IFN-γ. Guanidines 10 and 11 affect the bioenergetic metabolism of Leishmania, with selective elimination of parasites via a host-independent mechanism

Small Platforms, High Return: The Need to Enhance Investment in Small Satellites for Focused Science, Career Development, and Improved Equity

In the next decade, there is an opportunity for very high return on investment of relatively small budgets by elevating the priority of smallsat funding in heliophysics. We've learned in the past decade that these missions perform exceptionally well by traditional metrics, e.g., papers/year/\$M (Spence et al. 2022 -- arXiv:2206.02968). It is also well established that there is a "leaky pipeline" resulting in too little diversity in leadership positions (see the National Academies Report at https://www.nationalacademies.org/our-work/increasing-diversity-in-the-leadership-of-competed-space-missions). Prioritizing smallsat funding would significantly increase the number of opportunities for new leaders to learn -- a crucial patch for the pipeline and an essential phase of career development. At present, however, there are far more proposers than the available funding can support, leading to selection ratios that can be as low as 6% -- in the bottom 0.5th percentile of selection ratios across the history of ROSES. Prioritizing SmallSat funding and substantially increasing that selection ratio are the fundamental recommendations being made by this white paper.Comment: White paper submitted to the Decadal Survey for Solar and Space Physics (Heliophysics) 2024-2033; 6 pages, 1 figur

Leishmanicidal activity of an alkenylphenol from Piper malacophyllum is related to plasma membrane disruption

Leishmaniasis and Chagas disease are parasitic protozoan infections that affect the poorest population in the world, causing high mortality and morbidity. As a result of highly toxic and long-duration treatments, novel, safe and more efficacious drugs are essential. In this work, the methanol (MeOH) extract from the leaves of Piper malacophyllum (Piperaceae) was fractioned to afford one alkenylphenol, which was characterized as 4-[(3'E)-decenyl]phenol (gibbilimbol B) by spectroscopic methods. Anti-protozoan in vitro assays demonstrated for the first time that Leishmania (L.) infantum chagasi was susceptible to gibbilimbol B. with an in vitro EC50 of 23 mu g/mL against axenic promastigotes and an EC50 of 22 mu g/mL against intracellular amastigotes. Gibbilimbol B was also tested for anti-trypanosomal activity (Trypanosoma cruzi) and showed an EC50 value of 17 mu g/mL against trypomastigotes. To evaluate the cytotoxic parameters, this alkenylphenol was tested in vitro against NCTC cells, showing a CC50 of 59 mu g/mL and absent hemolytic activity at the highest concentration of 75 mu g/mL. Using the fluorescent probe SYTOX Green suggested that the alkenylphenol disrupted the Leishmania plasma membrane upon initial incubation. Further drug design studies aiming at derivatives could be a promising tool for the development of new therapeutic agents for leishmaniasis and Chagas disease. (C) 2012 Elsevier Inc. All rights reserved.FAPESPCNP

Soulamarin isolated from Calophyllum brasiliense (Clusiaceae) induces plasma membrane permeabilization of Trypanosoma cruzi and mytochondrial dysfunction.

Chagas disease is caused by the parasitic protozoan Trypanosoma cruzi. It has high mortality as well as morbidity rates and usually affects the poorer sections of the population. The development of new, less harmful and more effective drugs is a promising research target, since current standard treatments are highly toxic and administered for long periods. Fractioning of methanol (MeOH) extract of the stem bark of Calophyllum brasiliense (Clusiaceae) resulted in the isolation of the coumarin soulamarin, which was characterized by one- and two-dimensional (1)H- and (13)C NMR spectroscopy as well as ESI mass spectrometry. All data obtained were consistent with a structure of 6-hydroxy-4-propyl-5-(3-hydroxy-2-methyl-1-oxobutyl)-6″,6″-dimethylpyrane-[2″,3″:8,7]-benzopyran-2-one for soulamarin. Colorimetric MTT assays showed that soulamarin induces trypanocidal effects, and is also active against trypomastigotes. Hemolytic activity tests showed that soulamarin is unable to induce any observable damage to erythrocytes (cmax. = 1,300 µM). The lethal action of soulamarin against T. cruzi was investigated by using amino(4-(6-(amino(iminio)methyl)-1H-indol-2-yl)phenyl)methaniminium chloride (SYTOX Green and 1H,5H,11H,15H-Xantheno[2,3,4-ij:5,6,7-i'j']diquinolizin-18-ium, 9-[4-(chloromethyl)phenyl]-2,3,6,7,12,13,16,17-octahydro-chloride (MitoTracker Red) as fluorimetric probes. With the former, soulamarin showed dose-dependent permeability of the plasma membrane, relative to fully permeable Triton X-100-treated parasites. Spectrofluorimetric and fluorescence microscopy with the latter revealed that soulamarin also induced a strong depolarization (ca. 97%) of the mitochondrial membrane potential. These data demonstrate that the lethal action of soulamarin towards T. cruzi involves damages to the plasma membrane of the parasite and mitochondrial dysfunction without the additional generation of reactive oxygen species, which may have also contributed to the death of the parasites. Considering the unique mitochondrion of T. cruzi, secondary metabolites of plants affecting the bioenergetic system as soulamarin may contribute as scaffolds for the design of novel and selective drug candidates for neglected diseases, mainly Chagas disease

Development of a microfluidic paper-based analytical device for magnesium determination in saliva samples

In this work, a microfluidic paper-based analytical device (μPAD) was developed for magnesium determination in saliva samples. The idea was to develop a fast and simple method for biological magnesium quantification targeting saliva as an easy to collect and non-invasive alternative to blood or urine samples. The μPAD approach was chosen due to its advantages, namely ideally suited to conduct on-location determinations, and not requiring trained operators or specialized laboratory equipment. The developed μPAD was based on the colorimetric reaction between eriochrome cyanine and magnesium to form an intense orange/reddish colour product. The colour intensity was determined by image processing after digital scanning, made within 10 to 90 min after sample loading. Under optimal conditions, the dynamic concentration range was 82–247 μM, with detection and quantification limits of 62 μM and 81 μM, respectively. The device is stable for up to 3 months when stored in vacuum or in a modified nitrogen atmosphere. An accuracy assessment was made by comparing the results obtained using the developed μPAD with those from atomic absorption spectrometry (AAS). The relative difference between the two sets of results was below 5%.info:eu-repo/semantics/publishedVersio